485BPOS2012-05-3100007837402012-09-28MFS SERIES TRUST Xfalse2012-09-272012-09-28<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's performance.&#xA0;&#xA0;<br />During the most recent fiscal year, the fund's portfolio turnover rate was 10% of <br />the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000031672Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The fund's investment objective is to seek total return.</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br />&#xA0;&#xA0;<br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt><tt>In managing the fund, MFS (Massachusetts Financial Services Company, the fund's<br />investment adviser) employs an absolute return investment approach, which means<br />the fund seeks to earn a positive return regardless of market conditions. As <br />a result, if this strategy is successful, it is expected that the fund will<br />outperform the general equity market during periods of flat or negative market<br />performance, will underperform during periods of strong positive market<br />performance, and will typically produce less volatile returns than the general<br />equity market.<br />&#xA0;&#xA0;<br />MFS seeks to achieve the fund's objective by generating returns from a<br />combination of (1) individual security selection of primarily debt instruments<br />and (2) a tactical asset allocation overlay primarily using derivative<br />instruments to manage the fund's exposure to asset classes, markets and<br />currencies. Derivatives include futures, forward contracts, options, structured<br />securities, inverse floating rate instruments, and swaps.<br /> <br />The fund's performance may not be correlated with the performance of the asset<br />classes, markets or currencies represented by the individual investments<br />selected by MFS.<br />&#xA0;&#xA0;<br />Individual Security Selection:&#xA0;&#xA0;In selecting direct investments for the fund,<br />MFS normally invests the fund's assets primarily in debt instruments.<br />&#xA0;&#xA0;<br />Debt instruments include corporate bonds, U.S. Government securities,<br />asset-backed securities, municipal instruments, foreign government securities,<br />inflation-adjusted bonds, and other obligations to repay money borrowed.<br />&#xA0;&#xA0;<br />Of the fund's investments in debt instruments, MFS generally invests<br />substantially all of these investments in investment grade debt instruments.<br />&#xA0;&#xA0;<br />While MFS may invest the fund's assets in debt instruments of any effective<br />maturity, MFS generally focuses on short and intermediate term debt instruments.<br />&#xA0;&#xA0;<br />MFS may invest the fund's assets in U.S. and foreign securities, including<br />emerging market securities.<br />&#xA0;&#xA0;<br />While MFS may use derivatives for any investment purpose, to the extent MFS uses<br />derivatives as part of its individual security selection process, MFS expects to<br />use derivatives primarily to increase or decrease exposure to a particular<br />market, segment of the market, or security, to increase or decrease interest<br />rate or currency exposure, or as alternatives to direct investments.<br /> <br />MFS uses a bottom-up investment approach to buying and selling investments for<br />the fund. Investments are selected primarily based on fundamental analysis of<br />individual instruments and their issuers. Quantitative models that<br />systematically evaluate instruments may also be considered.<br />&#xA0;&#xA0;<br />Tactical Asset Allocation Overlay:&#xA0;&#xA0;MFS employs a top-down tactical asset<br />allocation process to adjust the fund's exposure to asset classes, markets <br />and currencies based on its assessment of the relative attractiveness of <br />such asset classes, markets and currencies. MFS manages the fund's exposure <br />to asset classes, markets and currencies primarily through the use of <br />derivative instruments based on its proprietary quantitative models.<br />&#xA0;&#xA0;<br />In managing the tactical overlay, MFS may increase or decrease the fund's<br />exposure to asset classes, markets and/or currencies resulting from MFS'<br />individual security selection based on MFS' assessment of the risk/return<br />potential of such asset classes, markets and/or currencies. MFS may also expose<br />the fund to asset classes, markets and/or currencies in which its individual<br />security selection has resulted in no or little exposure (e.g., commodity-related <br />investments, real estate-related investments, equity securities, inflation-adjusted <br />debt instruments). After taking into account the tactical overlay, the fund's <br />exposure to certain asset classes in which its individual security selection <br />has resulted in no or little exposure will normally fall within the following <br />ranges:<br />&#xA0;&#xA0;<br />Asset Class&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Range&#xA0;&#xA0;<br />U.S. and foreign equity securities&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xB1;15%<br />Inflation-adjusted debt instruments&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xB1;10%<br />Commodity-related investments&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xB1;10%<br />Real estate-related investments&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xB1; 5%<br />&#xA0;&#xA0;<br />After taking into account the tactical overlay, the fund's exposure to the less<br />than investment grade quality debt instrument (lower quality debt instrument)<br />and long term debt instrument asset classes may at times be significant, and the<br />fund may have significant exposure to issuers in a single country, a small<br />number of countries, or a particular geographic region.<br /> <br />MFS may adjust the fund's net exposure to asset classes, markets and/or<br />currencies by taking net short positions in an asset class, market or currency<br />if MFS believes the risk/return potential of such asset class, market or<br />currency is unattractive.&#xA0;&#xA0;Alternatively, MFS may cause the fund to take net<br />long positions in an asset class, market or currency if MFS believes such asset <br />class, market or currency appears attractive.<br /> <br />MFS may also use derivatives to seek to limit the fund's exposure to certain<br />extreme market events.<br />&#xA0;&#xA0;<br />MFS' tactical allocation process for the fund will typically make extensive use<br />of derivatives.</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your family invest,
or agree to invest in the future, at least $50,000 in MFS Funds.ExampleThe annual fund operating expenses for Class R5 shares are based on estimated "Other Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period.The bar chart and performance table are not included because the fund has not had a full calendar year of operations.Investment ObjectiveAs with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.10Performance Information50000Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br />&#xA0;&#xA0;<br />The principal risks of investing in the fund are:<br />&#xA0;&#xA0;<br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, its assessment of the risk/return potential of asset<br />classes, markets and currencies, and its adjustments to the fund's exposure to<br />asset classes, markets, and currencies through the use of derivatives may not<br />produce the intended results and/or can lead to an investment focus that results<br />in the fund underperforming other funds with similar investment strategies<br />and/or underperforming the markets in which the fund invests.<br />&#xA0;&#xA0;<br />Investment Strategy Risk:&#xA0;&#xA0;The fund's strategy to manage its exposure to asset<br />classes, markets, and currencies may not produce the intended results. In<br />addition, the strategies MFS may implement to limit the fund's exposure to<br />certain extreme market events may not work as intended, and the costs associated<br />with such strategies will reduce the fund's returns.<br /> <br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br />&#xA0;&#xA0;<br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br />&#xA0;&#xA0;<br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt <br />instruments.<br />&#xA0;&#xA0;<br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost. Derivatives can involve leverage.<br />&#xA0;&#xA0;<br />Foreign and Emerging Markets Risk: Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br /> <br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br />&#xA0;&#xA0;<br />Geographic Concentration Risk:&#xA0;&#xA0;The fund's performance could be closely tied to<br />the market, currency, economic, political, regulatory, geopolitical, or other<br />conditions in the countries or regions in which the fund invests and could be<br />more volatile than the performance of more geographically-diversified funds.<br /> <br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br />&#xA0;&#xA0;<br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. <br />If inflation is negative, principal and income can both decline.<br /> <br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /> <br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect <br />a single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br />&#xA0;&#xA0;<br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of <br />a commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br />&#xA0;&#xA0;<br />Tax Risk:&#xA0;&#xA0;In order to qualify as a regulated investment company (RIC) under <br />the Internal Revenue Code of 1986, as amended, the fund must meet certain <br />requirements regarding the source of its income, the diversification of its <br />assets, and the distribution of its income. If the fund were to fail to <br />qualify as a RIC and became subject to federal income tax, shareholders of <br />the fund would be subject to the risk of diminished returns.<br />&#xA0;&#xA0;<br />Real Estate-Related Investment Risk:&#xA0;&#xA0;The risks of investing in real<br />estate-related securities include certain risks associated with the direct<br />ownership of real estate and the real estate industry in general. These include<br />risks related to general, regional and local economic conditions; fluctuations<br />in interest rates; property tax rates, zoning laws, environmental regulations<br />and other governmental action; cash flow dependency; increased operating<br />expenses; lack of availability of mortgage funds; losses due to natural<br />disasters; overbuilding; losses due to casualty or condemnation; changes in<br />property values and rental rates; and other factors.&#xA0;&#xA0;The securities of smaller<br />real estate-related issuers can be more volatile and less liquid than securities<br />of larger issuers and their issuers can have more limited financial resources.<br /> <br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br />&#xA0;&#xA0;<br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /> <br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesPrincipal Investment Strategies<tt>The bar chart and performance table are not included because the fund has not<br />had a full calendar year of operations.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses for Class A, Class B, Class C, Class I,<br />Class R1, Class R2, Class R3, and Class R4 shares have been adjusted to reflect<br />current fee arrangements. The annual fund operating expenses for Class R5 shares<br />are based on estimated "Other Expenses" for the current fiscal year expressed as<br />a percentage of the fund's estimated average net assets during the period.<br />&#xA0;&#xA0;<br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-14 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000031672Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed by the
Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000031672Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000031672Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>MRNVX0.000091369-0.00401521<tt>R5</tt>6690.00640.00652013-09-300.00000.00890.0129<tt>Class R5 Shares</tt><tt>ALL R</tt>0.0000MRNUX0.000091369-0.00401521<tt>R4</tt>6690.00640.00652013-09-300.00000.00890.0129<tt>Class R4 Shares</tt><tt>ALL R</tt>0.0000MRNTX0.0000116447-0.00401801<tt>R3</tt>8020.00640.00652013-09-300.00250.01140.0154<tt>Class R3 Shares</tt><tt>ALL R</tt>0.0000MRNSX0.0000142524-0.00402072<tt>R2</tt>9320.00640.00652013-09-300.00500.01390.0179<tt>Class R2 Shares</tt><tt>ALL R</tt>0.0000MRNRX0.0000192677-0.00402595<tt>R1</tt>11890.00640.00652013-09-300.01000.01890.0229<tt>Class R1 Shares</tt><tt>ALL R</tt>0.0000MRNIX0.000091369-0.00401521<tt>I</tt>6690.00640.00652013-09-300.00000.00890.0129<tt>Class I Shares</tt><tt>I</tt>0.0000MRNCX0.0000292192677-0.00402595<tt>C</tt>11890.00640.00652013-09-3025956771189<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.01890.0229<tt>Class C Shares assuming redemption at end of period</tt><tt>C</tt>0.0100MRNBX0.0000592192977-0.00402406<tt>B</tt>13890.00640.00652013-09-3024066771189<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.01890.0229<tt>Class B Shares assuming redemption at end of period</tt><tt>B</tt>0.0400MRNAX0.0475586901-0.00402190<tt>A</tt>12390.00640.00652013-09-300.00250.01140.0154<tt>Class A Shares</tt><tt>A</tt>0.0100Because MFS may invest a relatively large percentage of the fund's assets in a single
issuer or small number of issuers, the fund's performance could be closely tied to the
value of that one issuer or issuers, and could be more volatile than the performance of
diversified funds.<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's<br />performance.&#xA0;&#xA0;During the most recent fiscal year, the fund's portfolio turnover<br />rate was 98% of the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000028956Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000028956Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The fund's investment objective is to seek total return with an emphasis on<br />current income, but also considering capital appreciation.</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br />&#xA0;&#xA0;<br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>MFS (Massachusetts Financial Services Company, the fund's investment adviser)<br />normally invests at least 80% of the fund's net assets in debt instruments of<br />U.S. and foreign issuers, including emerging markets issuers.<br />&#xA0;&#xA0;<br />While MFS may invest the fund's assets in debt instruments of any type, MFS<br />generally focuses on debt instruments of U.S. and foreign governments.<br />&#xA0;&#xA0;<br />MFS may invest up to 100% of the fund's assets in less than investment grade<br />quality debt instruments (lower quality debt instruments).<br /> <br />MFS may invest a large percentage of the fund's assets in issuers in a single<br />country, a small number of countries, or a particular geographic region.<br />&#xA0;&#xA0;<br />MFS may invest up to 35% of the fund's assets in any industry that accounts for<br />more than 20% of the global bond market.<br /> <br />The fund is a non-diversified fund. This means that MFS may invest a relatively<br />large percentage of the fund's assets in a single issuer or a small number of<br />issuers.<br />&#xA0;&#xA0;<br />While MFS may use derivatives for any investment purpose, to the extent MFS uses<br />derivatives, MFS expects to use derivatives primarily to increase or decrease<br />exposure to a particular market, segment of the market, or security, to increase<br />or decrease interest rate or currency exposure, or as alternatives to direct<br />investments. Derivatives include futures, forward contracts, options, structured<br />securities, inverse floating rate instruments, and swaps.<br />&#xA0;&#xA0;<br />MFS generally uses a top-down approach to buying and selling investments for the<br />fund. MFS allocates the fund's assets across countries and selects investments<br />primarily based on fundamental economic and financial analysis. Quantitative<br />models that systematically evaluate economic and financial factors may also be<br />considered. MFS may also use a bottom-up investment approach, particularly for<br />corporate debt instruments, selecting investments based on fundamental analysis<br />of individual instruments and their issuers.</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your family
invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.The annual fund operating expenses for Class R5 shares are based on estimated "Other Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.98Your actual after-tax returns will depend on your own tax situation, and may differ
from those shown. The after-tax returns shown are not relevant to investors who hold
their shares through tax-deferred arrangements, such as 401(k) plans or individual
retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may be required
to pay upon purchase or redemption of the fund's shares. If these sales charges were included,
they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local<br />taxes. Your actual after-tax returns will depend on your own tax situation, and<br />may differ from those shown. The after-tax returns shown are not relevant to<br />investors who hold their shares through tax-deferred arrangements, such as<br />401(k) plans or individual retirement accounts. The after-tax returns are shown<br />for only one of the fund's classes of shares, and after-tax returns for the<br />fund's other classes of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication of the
risks of investing in the fund by showing how the fund's performance over time compares
with that of a broad measure of market performance.<tt>The total return for the six-month period ended June 30, 2012 was 0.53%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 3.87%<br />(for the calendar quarter ended June 30, 2011) and the lowest quarterly return<br />was (0.07)% (for the calendar quarter ended March 31, 2011).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you may be <br />required to pay upon purchase or redemption of the fund's shares. If these sales <br />charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br />&#xA0;&#xA0;<br />The principal risks of investing in the fund are:<br />&#xA0;&#xA0;<br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br />&#xA0;&#xA0;<br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br />&#xA0;&#xA0;<br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about the <br />issuer, or the market or economy in general, than higher quality debt instruments.<br />&#xA0;&#xA0;<br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br />&#xA0;&#xA0;<br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br />&#xA0;&#xA0;<br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br />&#xA0;&#xA0;<br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on<br />inflation-adjusted debt instruments can be unpredictable and vary based on the<br />level of inflation. If inflation is negative, principal and income can both<br />decline.<br /><br />Geographic Concentration Risk:&#xA0;&#xA0;The fund's performance could be closely tied to<br />the market, currency, economic, political, regulatory, geopolitical, or other<br />conditions in the countries or regions in which the fund invests and could be<br />more volatile than the performance of more geographically-diversified funds.<br />&#xA0;&#xA0;<br />Non-Diversification Risk:&#xA0;&#xA0;Because MFS may invest a relatively large percentage<br />of the fund's assets in a single issuer or small number of issuers, the fund's<br />performance could be closely tied to the value of that one issuer or issuers,<br />and could be more volatile than the performance of diversified funds.<br /> <br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br />&#xA0;&#xA0;<br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br />&#xA0;&#xA0;<br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.<br />&#xA0;&#xA0;<br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br />&#xA0;&#xA0;<br />Investment Selection Risk:&#xA0;&#xA0;MFS' investment analysis and its selection of<br />investments may not produce the intended results and/or can lead to an<br />investment focus that results in the fund underperforming other funds with<br />similar investment strategies and/or underperforming the markets in which the<br />fund invests.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares,
and after-tax returns for the fund's other classes of shares will vary from
the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing how the fund's<br />performance over time compares with that of a broad measure of market<br />performance.<br />&#xA0;&#xA0;<br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses for Class A, Class B, Class C, Class I,<br />Class R1, Class R2, Class R3, and Class R4 shares have been adjusted to reflect<br />current fee arrangements. The annual fund operating expenses for Class R5 shares<br />are based on estimated "Other Expenses" for the current fiscal year expressed as<br />a percentage of the fund's estimated average net assets during the period.<br />&#xA0;&#xA0;<br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 9 of the fund's prospectus and "Waivers of Sales Charges" on page I-14 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000028956Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000028956Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed by the
Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000028956Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000028956Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparison (Reflects no deduction for fees, expenses or taxes) JPMorgan Global Government Bond Index (Unhedged)0.07220.09812010-06-02A Shares Returns After Taxes on Distributions and Sale of Fund Shares0.00660.03352010-06-02A Shares Returns After Taxes on Distributions-0.01150.03322010-06-02MGBOX0.0000R5 Shares Returns Before Taxes86270-0.00011048<tt>R5</tt>4700.05680.00250.00602013-09-300.00000.00840.0085<tt>Class R5 Shares </tt>0.08292010-06-02<tt>ALL R </tt>0.0000MGBNX0.0000R4 Shares Returns Before Taxes86270-0.00011048<tt>R4</tt>4700.05790.00250.00602013-09-300.00000.00840.0085<tt>Class R4 Shares</tt>0.08302010-06-02<tt>ALL R </tt>0.0000MGBMX0.0000R3 Shares Returns Before Taxes111349-0.00011339<tt>R3</tt>6050.05420.00250.00602013-09-300.00250.01090.0110<tt>Class R3 Shares</tt>0.07982010-06-02<tt>ALL R </tt>0.0000MGBLX0.0000R2 Shares Returns Before Taxes136427-0.00011623<tt>R2</tt>7380.05160.00250.00602013-09-300.00500.01340.0135<tt>Class R2 Shares</tt>0.07732010-06-02<tt>ALL R </tt>0.0000MGBKX0.0000R1 Shares Returns Before Taxes187581-0.00012168<tt>R1</tt>10000.04740.00250.00602013-09-300.01000.01840.0185<tt>Class R1 Shares</tt>0.07222010-06-02<tt>ALL R </tt>0.0000MGBJX0.0000I Shares Returns Before Taxes86270-0.00011048<tt>I</tt>4700.05680.00250.00602013-09-300.00000.00840.0085<tt>Class I Shares</tt>0.08292010-06-02<tt>I</tt>0.0000MGBDX0.0000C Shares Returns Before Taxes287187581-0.00012168<tt>C</tt>10000.03850.00250.00602013-09-3021685811000<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.01840.0185<tt>Class C Shares assuming redemption at end of period</tt>0.07222010-06-02<tt>C</tt>0.0100MGBBX0.0000B Shares Returns Before Taxes587187881-0.00011972<tt>B</tt>12000.00780.00250.00602013-09-3019725811000<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.01840.0185<tt>Class B Shares assuming redemption at end of period</tt>0.04782010-06-02<tt>B</tt>0.0400MGBAXthe lowest quarterly returnthe highest quarterly return0.04752012-06-30A Shares Returns Before Taxes5812011-06-30807-0.0007-0.00011751<tt>A</tt>10510.03870.00970.00250.00602013-09-302011-03-31The total return for the six-month period ended0.06010.00250.01090.0110<tt>Class A Shares</tt>0.05142010-06-020.0053<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's performance.&#xA0;&#xA0;<br />During the most recent fiscal year, the fund's portfolio turnover rate was 15% of <br />the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002517Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002517Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The fund's investment objective is to seek capital appreciation.</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /> <br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>MFS (Massachusetts Financial Services Company, the fund's investment adviser)<br />normally invests the fund's assets primarily in foreign equity securities,<br />including emerging market equity securities. Equity securities include common<br />stocks, preferred stocks, securities convertible into stocks, and depositary<br />receipts for those securities.<br /> <br />MFS may invest a large percentage of the fund's assets in issuers in a single<br />country, a small number of countries, or a particular geographic region.<br />&#xA0;&#xA0;<br />MFS focuses on investing the fund's assets in the stocks of companies it<br />believes are undervalued compared to their perceived worth (value companies).<br />&#xA0;&#xA0;<br />MFS may invest the fund's assets in companies of any size.<br />&#xA0;&#xA0;<br />MFS uses a bottom-up investment approach to buying and selling investments for<br />the fund. Investments are selected primarily based on fundamental analysis of<br />individual issuers. Quantitative models that systematically evaluate issuers may<br />also be considered.</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your family invest,
or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.15Your actual after-tax returns will depend on your own tax situation, and may differ
from those shown. The after-tax returns shown are not relevant to investors who hold
their shares through tax-deferred arrangements, such as 401(k) plans or individual
retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may be
required to pay upon purchase or redemption of the fund's shares. If these sales
charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local<br />taxes. Your actual after-tax returns will depend on your own tax situation, <br />and may differ from those shown. The after-tax returns shown are not relevant <br />to investors who hold their shares through tax-deferred arrangements, such as<br />401(k) plans or individual retirement accounts. The after-tax returns are shown<br />for only one of the fund's classes of shares, and after-tax returns for the<br />fund's other classes of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication of the
risks of investing in the fund by showing changes in the fund's performance over time and
how the fund's performance over time compares with that of a broad measure of market
performance and one or more other measures of performance for markets in which the
fund may invest.<tt>The total return for the six-month period ended June 30, 2012 was 6.11%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 22.56%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (16.30)% (for the calendar quarter ended September 30, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that <br />you may be required to pay upon purchase&#xA0;&#xA0;or redemption of the fund's shares. <br />If these sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br />&#xA0;&#xA0;<br />The principal risks of investing in the fund are:<br />&#xA0;&#xA0;<br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect <br />a single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br />&#xA0;&#xA0;<br />Value Company Risk:&#xA0;&#xA0;The stocks of value companies can continue to be<br />undervalued for long periods of time and not realize their expected value and<br />can be more volatile than the market in general.<br />&#xA0;&#xA0;<br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br />&#xA0;&#xA0;<br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br />&#xA0;&#xA0;<br />Geographic Concentration Risk:&#xA0;&#xA0;The fund's performance could be closely tied to<br />the market, currency, economic, political, regulatory, geopolitical, or other<br />conditions in the countries or regions in which the fund invests and could be<br />more volatile than the performance of more geographically-diversified funds.<br />&#xA0;&#xA0;<br />Investment Selection Risk:&#xA0;&#xA0;MFS' investment analysis and its selection of<br />investments may not produce the intended results and/or can lead to an<br />investment focus that results in the fund underperforming other funds with<br />similar investment strategies and/or underperforming the markets in which the<br />fund invests.<br />&#xA0;&#xA0;<br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br />&#xA0;&#xA0;<br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares,
and after-tax returns for the fund's other classes of shares will vary from
the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in the<br />fund's performance over time and how the fund's performance over time compares<br />with that of a broad measure of market performance and one or more other<br />measures of performance for markets in which the fund may invest.<br />&#xA0;&#xA0;<br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses have been adjusted to reflect current fee<br />arrangements.<br />&#xA0;&#xA0;<br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 7 of the fund's prospectus and "Waivers of Sales Charges" on page I-15 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002517Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002517Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed by
the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002517Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002517Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI EAFE (Europe, Australasia, Far East) Index (gross div)-0.1173-0.04260.0512Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI EAFE (Europe, Australasia, Far East) Value Index (gross div)-0.1165-0.05770.0553A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.0455-0.01470.0662A Shares Returns After Taxes on Distributions-0.0768-0.02310.0691MINHX0.0000R4 Shares Returns Before Taxes983061178<tt>R4</tt>531-0.01720.00180.0078-0.00270.00000.08680.0096<tt>Class R4 Shares</tt><tt>ALL R </tt>0.0000MINGX0.0000R3 Shares Returns Before Taxes1233841466<tt>R3</tt>665-0.01920.00180.0078-0.00500.00250.08410.0121<tt>Class R3 Shares</tt><tt>ALL R </tt>0.0000MINFX0.0000R2 Shares Returns Before Taxes1494621746<tt>R2</tt>797-0.02180.00180.0078-0.00760.00500.08140.0146<tt>Class R2 Shares</tt><tt>ALL R </tt>0.0000MINRX0.0000R1 Shares Returns Before Taxes1996152285<tt>R1</tt>1057-0.02700.00180.0078-0.01250.01000.07600.0196<tt>Class R1 Shares</tt><tt>ALL R </tt>0.0000MINJX0.0000R5 Shares Returns Before Taxes882741061<tt>R5</tt>477-0.01810.00080.0078-0.00340.00000.08580.0086<tt>Class R5 Shares</tt><tt>ALL R </tt>0.0000MINIX0.0000I Shares Returns Before Taxes983061178<tt>I</tt>531-0.01690.00180.0078-0.00250.00000.08690.0096<tt>Class I Shares</tt><tt>I</tt>0.0000MGICX0.0000C Shares Returns Before Taxes2991996152285<tt>C</tt>1057-0.03630.00180.00782285-0.01256151057<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.07600.0196<tt>Class C Shares assuming redemption at end of period</tt><tt>C</tt>0.0100MGIBX0.0000B Shares Returns Before Taxes5991999152091<tt>B</tt>1257-0.06540.00180.00782091-0.01586151057<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.07750.0196<tt>Class B Shares assuming redemption at end of period</tt><tt>B</tt>0.0400MGIAX-0.0695lowest quarterly returnthe highest quarterly return0.05752012-06-30A Shares Returns Before Taxes6912009-06-30937-0.16300.26770.09131957<tt>A</tt>12020.07150.2256-0.07600.0018-0.31910.00782008-09-300.2464-0.01720.1425The total return for the six-month period ended-0.01960.32030.00250.07650.01210.2808<tt>Class A Shares</tt>0.0611<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's performance. <br />During the most recent fiscal year, the fund's portfolio turnover rate was 39% of <br />the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002516Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002516Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The fund's investment objective is to seek capital appreciation.</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /> <br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>MFS (Massachusetts Financial Services Company, the fund's investment adviser)<br />normally invests the fund's assets primarily in foreign equity securities,<br />including emerging market equity securities. Equity securities include common<br />stocks, preferred stocks, securities convertible into stocks, and depositary<br />receipts for those securities.<br /> <br />MFS may invest a large percentage of the fund's assets in issuers in a single<br />country, a small number of countries, or a particular geographic region.<br /> <br />MFS focuses on investing the fund's assets in the stocks of companies it<br />believes to have above average earnings growth potential compared to other<br />companies (growth companies).<br />&#xA0;&#xA0;<br />MFS may invest the fund's assets in companies of any size.<br />&#xA0;&#xA0;<br />MFS uses a bottom-up investment approach to buying and selling investments for<br />the fund. Investments are selected primarily based on fundamental analysis of<br />individual issuers. Quantitative models that systematically evaluate issuers may<br />also be considered.</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your family invest,
or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.39Your actual after-tax returns will depend on your own tax situation, and may differ
from those shown. The after-tax returns shown are not relevant to investors who hold
their shares through tax-deferred arrangements, such as 401(k) plans or individual
retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may be
required to pay upon purchase or redemption of the fund's shares. If these sales
charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local<br />taxes. Your actual after-tax returns will depend on your own tax situation, and<br />may differ from those shown. The after-tax returns shown are not relevant to<br />investors who hold their shares through tax-deferred arrangements, such as<br />401(k) plans or individual retirement accounts. The after-tax returns are shown<br />for only one of the fund's classes of shares, and after-tax returns for the<br />fund's other classes of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication of
the risks of investing in the fund by showing changes in the fund's performance over
time and how the fund's performance over time compares with that of a broad measure
of market performance.<tt>The total return for the six-month period ended June 30, 2012 was 6.25%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 23.27%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (19.64)% (for the calendar quarter ended September 30, 2011).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you may <br />be required to pay upon purchase or redemption of the fund's shares. If these <br />sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br />&#xA0;&#xA0;<br />The principal risks of investing in the fund are:<br />&#xA0;&#xA0;<br />Stock Market/Company Risk: Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect <br />a single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br />&#xA0;&#xA0;<br />Foreign and Emerging Markets Risk: Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br /> <br />Currency Risk: The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /> <br />Geographic Concentration Risk: The fund's performance could be closely tied to<br />the market, currency, economic, political, regulatory, geopolitical, or other<br />conditions in the countries or regions in which the fund invests and could be<br />more volatile than the performance of more geographically-diversified funds.<br />&#xA0;&#xA0;<br />Growth Company Risk: The stocks of growth companies can be more sensitive to<br />the company's earnings and more volatile than the market in general.<br />&#xA0;&#xA0;<br />Investment Selection Risk: MFS' investment analysis and its selection of<br />investments may not produce the intended results and/or can lead to an<br />investment focus that results in the fund underperforming other funds with<br />similar investment strategies and/or underperforming the markets in which the<br />fund invests.<br />&#xA0;&#xA0;<br />Counterparty and Third Party Risk: Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br />&#xA0;&#xA0;<br />Liquidity Risk: It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares, and after-tax
returns for the fund's other classes of shares will vary from the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in the<br />fund's performance over time and how the fund's performance over time compares<br />with that of a broad measure of market performance.<br />&#xA0;&#xA0;<br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses have been adjusted to reflect current fee<br />arrangements.<br />&#xA0;&#xA0;<br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 7 of the fund's prospectus and "Waivers of Sales Charges" on page I-16 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002516Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002516Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed by the
Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002516Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002516Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparison (Reflects no deduction for fees, expenses or taxes) MSCI All Country World (ex-US) Growth Index (gross div)-0.1393-0.01840.0594A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.1011-0.01310.0557A Shares Returns After Taxes on Distributions-0.1596-0.02000.0594MGRTX0.0000R3 Shares Returns Before Taxes1394341646<tt>R3</tt>750-0.10800.00270.0085-0.00370.00250.07140.0137<tt>Class R3 Shares</tt><tt>ALL R</tt>0.0000MGRQX0.0000R2 Shares Returns Before Taxes1655111922<tt>R2</tt>881-0.11060.00270.0085-0.00620.00500.06870.0162<tt>Class R2 Shares</tt><tt>ALL R</tt>0.0000MGRRX0.0000R1 Shares Returns Before Taxes2156642452<tt>R1</tt>1139-0.11520.00270.0085-0.01120.01000.06330.0212<tt>Class R1 Shares</tt><tt>ALL R</tt>0.0000MGRVX0.0000R4 Shares Returns Before Taxes1143561363<tt>R4</tt>617-0.10630.00270.0085-0.00130.00000.07400.0112<tt>Class R4 Shares</tt><tt>ALL R</tt>0.0000MGRDX0.0000R5 Shares Returns Before Taxes1043251248<tt>R5</tt>563-0.10700.00170.0085-0.00220.00000.07290.0102<tt>Class R5 Shares</tt><tt>ALL R</tt>0.0000MQGIX0.0000I Shares Returns Before Taxes1143561363<tt>I</tt>617-0.10620.00270.0085-0.00120.00000.07630.0112<tt>Class I Shares</tt><tt>I</tt>0.0000MGRCX0.0000C Shares Returns Before Taxes3152156642452<tt>C</tt>1139-0.12420.00270.00852452-0.01126641139<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.06330.0212<tt>Class C Shares assuming redemption at end of period</tt><tt>C</tt>0.0100MGRBX0.0000B Shares Returns Before Taxes6152159642261<tt>B</tt>1339-0.15030.00270.00852261-0.01476641139<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.06490.0212<tt>Class B Shares assuming redemption at end of period</tt><tt>B</tt>0.0400MGRAX-0.1213lowest quarterly returnthe highest quarterly return0.05752012-06-30A Shares Returns Before Taxes7062009-06-30984-0.19640.17540.14992127<tt>A</tt>12820.15900.2327-0.15970.0027-0.40100.00852011-09-300.3765-0.01580.1395The total return for the six-month period ended-0.10850.36030.00250.06390.01370.2572<tt>Class A Shares</tt>0.0625<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's performance.&#xA0;&#xA0;<br />During the most recent fiscal year, the fund's portfolio turnover rate was 8% of <br />the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002515Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002515Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The fund's investment objective is to seek capital appreciation.</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table. Reflects no deduction for fees, expenses or taxes<tt>The fund is designed to provide diversification within the international asset<br />class by investing the majority of its assets in other mutual funds advised by<br />MFS (Massachusetts Financial Services Company, the fund's Investment adviser),<br />referred to as underlying funds. The underlying funds are selected based on<br />underlying fund classifications, historical risk, performance, and other<br />factors. MFS seeks to diversify the fund's investments in terms of market<br />capitalization (by including large, mid, and/or small cap underlying funds), by<br />style (by including both growth and value underlying funds), and by geographic<br />region (by including developed and emerging market underlying funds). However,<br />MFS may invest a relatively large percentage of the underlying funds' assets in<br />a single country, a small number of countries, or a particular geographic region. <br />As of September 28, 2012, the fund's target allocation among underlying funds was:<br />&#xA0;&#xA0;<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;10%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30%</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your
family invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.08Your actual after-tax returns will depend on your own tax situation, and may differ from
those shown. The after-tax returns shown are not relevant to investors who hold their shares
through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may be
required to pay upon purchase or redemption of the fund's shares. If these sales
charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local<br />taxes. Your actual after-tax returns will depend on your own tax situation, and<br />may differ from those shown. The after-tax returns shown are not relevant to<br />investors who hold their shares through tax-deferred arrangements, such as<br />401(k) plans or individual retirement accounts. The after-tax returns are shown<br />for only one of the fund's classes of shares, and after-tax returns for the<br />fund's other classes of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication of
the risks of investing in the fund by showing changes in the fund's performance over
time and how the fund's performance over time compares with that of a broad measure
of market performance.<tt>The total return for the six-month period ended June 30, 2012 was 5.68%.&#xA0;&#xA0;During<br />the period(s) shown in the bar chart, the highest quarterly return was 23.90%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (19.72)% (for the calendar quarter ended September 30, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you may <br />be required to pay upon purchase or redemption of the fund's shares. If these <br />sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br />&#xA0;&#xA0;<br />The principal risks of investing in the fund are:<br />&#xA0;&#xA0;<br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br />&#xA0;&#xA0;<br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect a<br />single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br />&#xA0;&#xA0;<br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br />&#xA0;&#xA0;<br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br />&#xA0;&#xA0;<br />Geographic Concentration Risk:&#xA0;&#xA0;The fund's performance could be closely tied to<br />the market, currency, economic, political, regulatory, geopolitical, or other<br />conditions in the countries or regions in which the fund invests and could be<br />more volatile than the performance of more geographically-diversified funds.<br />&#xA0;&#xA0;<br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost. Derivatives can involve leverage.<br />&#xA0;&#xA0;<br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br />&#xA0;&#xA0;<br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third <br />party's ability to perform in accordance with the terms of the transaction.&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br /> <br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares, and after-tax
returns for the fund's other classes of shares will vary from the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in the<br />fund's performance over time and how the fund's performance over time compares<br />with that of a broad measure of market performance.<br /> <br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund.&#xA0;&#xA0;Expenses have been adjusted to reflect current fee<br />arrangements.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 8 of the fund's prospectus and "Waivers of Sales Charges" on page I-14 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002515Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002515Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed by
the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002515Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002515Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparison (Reflects no deduction for fees, expenses or taxes) MSCI All Country World (ex-US) Index (gross div)-0.1333-0.02480.05982004-09-30A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.0934-0.02350.04702004-09-30A Shares Returns After Taxes on Distributions-0.1472-0.03290.04862004-09-30MDIHX0.0000R3 Shares Returns Before Taxes134425-0.00031621<tt>R3</tt>737-0.09430.00130.00002013-09-30-0.01480.00250.01320.0135<tt>Class R3 Shares </tt>0.06492004-09-300.0097<tt>ALL R</tt>0.0000MDIKX0.0000R2 Shares Returns Before Taxes160502-0.00031898<tt>R2</tt>868-0.09700.00130.00002013-09-30-0.01720.00500.01570.0160<tt>Class R2 Shares</tt>0.06222004-09-300.0097<tt>ALL R</tt>0.0000MDIOX0.0000R1 Shares Returns Before Taxes210655-0.00032429<tt>R1</tt>1126-0.10100.00130.00002013-09-30-0.02210.01000.02070.0210<tt>Class R1 Shares</tt>0.05712004-09-300.0097<tt>ALL R</tt>0.0000MDIJX0.0000I Shares Returns Before Taxes109347-0.00031338<tt>I</tt>603-0.09170.00130.00002013-09-30-0.01180.00000.01070.0110<tt>Class I Shares</tt>0.06852004-09-300.0097<tt>I</tt>0.0000MDIGX0.0000C Shares Returns Before Taxes310210655-0.00032429<tt>C</tt>1126-0.10970.00130.00002013-09-302429-0.02186551126<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.02070.0210<tt>Class C Shares assuming redemption at end of period</tt>0.05782004-09-300.0097<tt>C</tt>0.0100MDIFX0.0000B Shares Returns Before Taxes610210955-0.00032237<tt>B</tt>1326-0.13710.00130.00002013-09-302237-0.02526551126<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.02070.0210<tt>Class B Shares assuming redemption at end of period</tt>0.05792004-09-300.0097<tt>B</tt>0.0400MDINX0.0000529C Shares Returns Before Taxes315215672-0.00082521<tt>529C</tt>1165-0.11100.00230.00002014-09-302521-0.02306721165<tt>Class 529C Shares Assuming no redemption at end of period</tt>0.01000.02120.0220<tt>Class 529C Shares Assuming redemption at end of period</tt>0.05612004-09-300.0097<tt>529C</tt>0.0100MDIMX0.0000529B Shares Returns Before Taxes615215972-0.00082331<tt>529B</tt>1365-0.13710.00230.00002014-09-302331-0.02666721165<tt>Class 529B Shares assuming no redemption at end of period</tt>0.01000.02120.0220<tt>Class 529B Shares assuming redemption at end of period</tt>0.05602004-09-300.0097<tt>529B</tt>0.0400MDIEX0.0575529A Shares Returns Before Taxes706992-0.00082197<tt>529A</tt>1307-0.14710.00230.00002014-09-30-0.02790.00250.01370.0145<tt>Class 529A Shares</tt>0.05452004-09-300.0097<tt>529A</tt>0.0000MDITX0.0000R4 Shares Returns Before Taxes109347-0.00031338<tt>R4</tt>603-0.09130.00130.00002013-09-30-0.01240.00000.01070.0110<tt>Class R4 Shares</tt>0.06782004-09-300.0097<tt>ALL R</tt>0.0000MDIDXthe lowest quarterly returnthe highest quarterly return0.05752012-06-30A Shares Returns Before Taxes7022009-06-30975-0.1972-0.00030.13202103<tt>A</tt>12690.12770.2390-0.14610.0013-0.40250.00002013-09-302008-09-300.3421-0.02650.1665The total return for the six-month period ended-0.09400.00250.01320.01350.2711<tt>Class A Shares</tt>0.05652004-09-300.05680.0097<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.&#xA0;&#xA0;During the most recent fiscal year, the fund's portfolio <br />turnover rate was 7% of the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002514Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002514Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The investment objective of the fund is to seek a high level of total return<br />consistent with a greater than moderate level of risk relative to the other MFS<br />Asset Allocation Funds.&#xA0;&#xA0;(The MFS Asset Allocation Funds currently include the<br />MFS Conservative Allocation Fund, MFS Moderate Allocation Fund, MFS Growth<br />Allocation Fund, and MFS Aggressive Growth Allocation Fund.)</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>The fund is designed to provide diversification among different asset classes by<br />investing its assets in other mutual funds advised by MFS (Massachusetts<br />Financial Services Company, the fund's investment adviser), referred to as<br />underlying funds. The underlying funds are selected following a two stage asset<br />allocation process. The first stage is a strategic asset allocation to determine<br />the percentage of the fund's assets to be invested in the general asset classes<br />of Bond Funds, International Stock Funds, and U.S. Stock Funds, as well as an<br />allocation to underlying funds that have less traditional investment strategies<br />that MFS believes provide diversification benefits when added to a portfolio<br />consisting of stock and bond funds (referred to as Specialty Funds). The second<br />stage involves the actual selection of underlying funds to represent the asset<br />classes based on underlying fund classifications, historical risk, performance,<br />and other factors. Within the stock fund allocations, MFS seeks to diversify<br />globally (by including domestic and international underlying funds), in terms of<br />market capitalization (by including large, mid, and small capitalization<br />underlying funds), and by style (by including both growth and value underlying<br />funds). Within the bond fund allocation, MFS includes underlying funds with<br />varying degrees of interest rate and credit exposure.<br /><br />As of September 28, 2012, the fund's target allocation among asset classes and<br />the underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%<br />MFS Emerging Markets Debt Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Global Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS High Income Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Absolute Return Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;52%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;11%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;9%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;9%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;11%</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your
family invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.07Your actual after-tax returns will depend on your own tax situation, and may differ
from those shown. The after-tax returns shown are not relevant to investors who hold
their shares through tax-deferred arrangements, such as 401(k) plans or individual
retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may
be required to pay upon purchase or redemption of the fund's shares. If these
sales charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local taxes. <br />Your actual after-tax returns will depend on your own tax situation, and may <br />differ from those shown. The after-tax returns shown are not relevant to investors <br />who hold their shares through tax-deferred arrangements, such as 401(k) plans or <br />individual retirement accounts. The after-tax returns are shown for only one of <br />the fund's classes of shares, and after-tax returns for the fund's other classes <br />of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication
of the risks of investing in the fund by showing changes in the fund's performance
over time and how the fund's performance over time compares with that of a broad
measure of market performance and one or more other measures of performance for
markets in which the fund may invest.<tt>The total return for the six-month period ended June 30, 2012 was 6.92%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 17.14%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (20.20)% (for the calendar quarter ended December 31, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you <br />may be required to pay upon purchase or redemption of the fund's shares. If <br />these sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential <br />of asset classes and underlying funds may not produce the intended results <br />and/or can lead to an investment focus that results in the fund underperforming <br />other funds with similar investment strategies and/or underperforming the markets <br />in which the fund invests.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect a<br />single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the <br />U.S. market. Emerging markets can have less developed markets and less developed <br />legal, regulatory, and accounting systems, and greater political, social, and <br />economic instability than developed markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /> <br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about the <br />issuer, or the market or economy in general, than higher quality debt instruments.<br /> <br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /> <br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /> <br />Real Estate-Related Investment Risk:&#xA0;&#xA0;The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real estate <br />and the real estate industry in general. These include risks related to general, <br />regional and local economic conditions; fluctuations in interest rates; property <br />tax rates, zoning laws, environmental regulations and other governmental action; <br />cash flow dependency; increased operating expenses; lack of availability of mortgage <br />funds; losses due to natural disasters; overbuilding; losses due to casualty or <br />condemnation; changes in property values and rental rates; and other factors.&#xA0;&#xA0;The <br />securities of smaller real estate-related issuers can be more volatile and less <br />liquid than securities of larger issuers and their issuers can have more limited <br />financial resources.<br /> <br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /> <br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /> <br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /> <br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares, and
after-tax returns for the fund's other classes of shares will vary from the returns
shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in <br />the fund's performance over time and how the fund's performance over <br />time compares with that of a broad measure of market performance and <br />one or more other measures of performance for markets in which the fund <br />may invest.<br /><br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses have been adjusted to reflect current fee<br />arrangements.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-20 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002514Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002514Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed
by the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002514Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002514Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Growth Allocation Fund Blended Index-0.00240.00580.05332002-06-28Index Comparisons (Reflects no deduction for fees, expenses or taxes) Standard & Poor's 500 Stock Index0.0211-0.00250.04592002-06-28A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.0496-0.00050.04332002-06-28A Shares Returns After Taxes on Distributions-0.0846-0.00490.04612002-06-28MAGEX0.0000R3 Shares Returns Before Taxes1193720.00001420<tt>R3</tt>644-0.02330.00110.00000.01510.00250.01170.0117<tt>Class R3 Shares</tt>0.05912002-06-280.0081<tt>ALL R</tt>0.0000MGALX0.0000R2 Shares Returns Before Taxes1454490.00001702<tt>R2</tt>776-0.02580.00110.00000.01250.00500.01420.0142<tt>Class R2 Shares</tt>0.05612002-06-280.0081<tt>ALL R</tt>0.0000MAGMX0.0000R1 Shares Returns Before Taxes1956030.00002243<tt>R1</tt>1037-0.03000.00110.00000.00770.01000.01920.0192<tt>Class R1 Shares</tt>0.05132002-06-280.0081<tt>ALL R</tt>0.0000MGWIX0.0000I Shares Returns Before Taxes942930.00001131<tt>I</tt>509-0.02010.00110.00000.01800.00000.00920.0092<tt>Class I Shares</tt>0.06282002-06-280.0081<tt>I</tt>0.0000MCGWX0.0000C Shares Returns Before Taxes2951956030.00002243<tt>C</tt>1037-0.04060.00110.000022430.00786031037<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.01920.0192<tt>Class C Shares assuming redemption at end of period</tt>0.05222002-06-280.0081<tt>C</tt>0.0100MBGWX0.0000B Shares Returns Before Taxes5951959030.00002048<tt>B</tt>1237-0.06900.00110.000020480.00446031037<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.01920.0192<tt>Class B Shares assuming redemption at end of period</tt>0.05342002-06-280.0081<tt>B</tt>0.0400ECGWX0.0000529C Shares Returns Before Taxes 300200629-0.00052344<tt>529C</tt>1083-0.04100.00210.00002013-09-3023440.00656291083<tt>Class 529C Shares assuming no redemption at end of period</tt>0.01000.01970.0202<tt>Class 529C Shares assuming redemption at end of period</tt>0.05022002-06-280.0081<tt>529C</tt>0.0100EBGWX0.0000529B Shares Returns Before Taxes600200929-0.00052151<tt>529B</tt>1283-0.06880.00210.00002013-09-3021510.00316291083<tt>Class 529B Shares assuming no redemption at end period</tt>0.01000.01970.0202<tt>Class 529B Shares assuming redemption at end of period</tt>0.05132002-06-280.0081<tt>529B</tt>0.0400EAGWX0.0575529A Shares Returns Before Taxes692950-0.00052017<tt>529A</tt>1227-0.07960.00210.00002013-09-300.00180.00250.01220.0127<tt>Class 529A Shares</tt>0.05082002-06-280.0081<tt>529A</tt>0.0000MAGJX0.0000R4 Shares Returns Before Taxes942930.00001131<tt>R4</tt>509-0.02090.00110.00000.01790.00000.00920.0092<tt>Class R4 Shares</tt>0.06222002-06-280.0081<tt>ALL R</tt>0.0000MAGWXlowest quarterly returnhighest quarterly return0.05752012-06-30A Shares Returns Before Taxes6872009-06-30925-0.20200.13750.00000.16711914<tt>A</tt>11820.08850.1714-0.07940.0011-0.34420.00002008-12-310.32330.00300.0666The total return for the six-month period ended-0.02330.26160.00250.01170.01170.1261<tt>Class A Shares</tt>0.05282002-06-280.06920.0081<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.&#xA0;&#xA0;During the most recent fiscal year, the fund's portfolio <br />turnover rate was 28% of the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002512Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002512Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The fund's investment objective is to seek capital appreciation.</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>MFS (Massachusetts Financial Services Company, the fund's investment adviser)<br />normally invests at least 80% of the fund's net assets in equity securities <br />of issuers that are tied economically to emerging market countries. Emerging <br />market countries include countries located in Latin America, Asia, Africa, <br />the Middle East, and developing countries of Europe, primarily Eastern Europe. <br />MFS may also invest in equity securities of issuers that are not tied <br />economically to emerging market countries.<br /><br />Equity securities include common stocks, preferred stocks, securities<br />convertible into stocks, and depositary receipts for those securities.<br /><br />MFS may invest the fund's assets in companies of any size.<br /> <br />MFS may invest a large percentage of the fund's assets in issuers in a single<br />country, a small number of countries, or a particular geographic region.<br /><br />MFS may invest a relatively large percentage of the fund's assets in a single<br />issuer or a small number of issuers.<br /> <br />MFS uses a bottom-up investment approach to buying and selling investments for<br />the fund. Investments are selected primarily based on fundamental analysis of<br />individual issuers. Quantitative models that systematically evaluate issuers may<br />also be considered.</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your
family invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.The annual fund operating expenses for Class R5 shares are based on estimated "Other Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.28Your actual after-tax returns will depend on your own tax situation, and
may differ from those shown. The after-tax returns shown are not relevant
to investors who hold their shares through tax-deferred arrangements, such
as 401(k) plans or individual retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may
be required to pay upon purchase or redemption of the fund's shares. If these
sales charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local taxes. <br />Your actual after-tax returns will depend on your own tax situation, and may <br />differ from those shown. The after-tax returns shown are not relevant to investors <br />who hold their shares through tax-deferred arrangements, such as 401(k) plans or <br />individual retirement accounts. The after-tax returns are shown for only one of <br />the fund's classes of shares, and after-tax returns for the fund's other classes <br />of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication of
the risks of investing in the fund by showing changes in the fund's performance over
time and how the fund's performance over time compares with that of a broad measure
of market performance.<tt>The total return for the six-month period ended June 30, 2012 was 5.55%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 30.53%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (30.59)% (for the calendar quarter ended September 30, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that <br />you may be required to pay upon purchase or redemption of the fund's <br />shares. If these sales charges were included, they would reduce the<br />returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect <br />a single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Geographic Concentration Risk:&#xA0;&#xA0;The fund's performance could be closely tied to<br />the market, currency, economic, political, regulatory, geopolitical, or other<br />conditions in the countries or regions in which the fund invests and could be<br />more volatile than the performance of more geographically-diversified funds.<br /><br />Issuer Focus Risk:&#xA0;&#xA0;The fund's performance could be more volatile than the<br />performance of more diversified funds.<br /><br />Investment Selection Risk:&#xA0;&#xA0;MFS' investment analysis and its selection of<br />investments may not produce the intended results and/or can lead to an<br />investment focus that results in the fund underperforming other funds with<br />similar investment strategies and/or underperforming the markets in which the<br />fund invests.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares,
and after-tax returns for the fund's other classes of shares will vary from
the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in <br />the fund's performance over time and how the fund's performance over <br />time compares with that of a broad measure of market performance.<br /><br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses for Class A, Class B, Class C, Class I,<br />Class R1, Class R2, Class R3, and Class R4 shares have been adjusted to reflect<br />current fee arrangements. The annual fund operating expenses for Class R5 shares<br />are based on estimated "Other Expenses" for the current fiscal year expressed as<br />a percentage of the fund's estimated average net assets during the period.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 7 of the fund's prospectus and "Waivers of Sales Charges" on page I-14 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002512Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002512Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed
by the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002512Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002512Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparison (Reflects no deduction for fees, expenses or taxes) MSCI Emerging Markets Index (gross div)-0.18170.02700.1420A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.1501-0.00760.1083A Shares Returns After Taxes on Distributions-0.2337-0.01700.1136MEMJX0.0000R5 Shares Returns Before Taxes138433-0.00011645<tt>R5</tt>749-0.18610.00330.01042013-09-300.00510.00000.13170.01360.0137<tt>Class R5 Shares</tt><tt>ALL R </tt>0.0000MEMHX0.0000R4 Shares Returns Before Taxes149464-0.00011757<tt> R4</tt>802-0.18610.00430.01042013-09-300.00520.00000.13180.01460.0147<tt>Class R4 Shares</tt><tt>ALL R</tt>0.0000MEMGX0.0000R3 Shares Returns Before Taxes174541-0.00012029<tt>R3</tt>932-0.18820.00430.01042013-09-300.00260.00250.12890.01710.0172<tt>Class R3 Shares</tt><tt>ALL R</tt>0.0000MEMFX0.0000R2 Shares Returns Before Taxes199617-0.00012295<tt>R2 </tt>1061-0.19020.00430.01042013-09-300.00020.00500.12610.01960.0197<tt>Class R2 Shares</tt><tt>ALL R</tt>0.0000MEMRX0.0000R1 Shares Returns Before Taxes249769-0.00012805<tt>R1</tt>1315-0.19400.00430.01042013-09-30-0.00480.01000.12050.02460.0247<tt>Class R1 Shares</tt><tt>ALL R</tt>0.0000MEMIX0.0000I Shares Returns Before Taxes149464-0.00011757<tt>I</tt>802-0.18610.00430.01042013-09-300.00510.00000.13170.01460.0147<tt>Class I Shares</tt><tt>I</tt>0.0000MEMCX0.0000C Shares Returns Before Taxes349249769-0.00012805<tt>C</tt>1315-0.20200.00430.01042013-09-302805-0.00487691315<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.12050.02460.0247<tt>Class C Shares assuming redemption at end of period</tt><tt>C</tt>0.0100MEMBX0.0000B Shares Returns Before Taxes6492491069-0.00012621<tt>B</tt>1515-0.22650.00430.01042013-09-302621-0.00787691315<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.12220.02460.0247<tt>Class B Shares assuming redemption at end of period</tt><tt>B</tt>0.0400MEMAX-0.0284lowest quarterly returnhighest quarterly return0.05752012-06-30A Shares Returns Before Taxes7392009-06-301085-0.30590.2671-0.00010.23072488<tt>A</tt>14540.35460.3053-0.23480.0043-0.55550.01042013-09-302008-09-300.6810-0.00950.3548The total return for the six-month period ended-0.18810.52020.00250.12110.01710.01720.2975<tt>Class A Shares</tt>0.0555<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's<br />performance.&#xA0;&#xA0;During the most recent fiscal year, the fund's portfolio turnover<br />rate was 4% of the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002510Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002510Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The investment objective of the fund is to seek a high level of total return<br />consistent with a conservative level of risk relative to the other MFS Asset<br />Allocation Funds.&#xA0;&#xA0;(The MFS Asset Allocation Funds currently include the MFS<br />Conservative Allocation Fund, MFS Moderate Allocation Fund, MFS Growth<br />Allocation Fund, and MFS Aggressive Growth Allocation Fund.)</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>The fund is designed to provide diversification among different asset classes by<br />investing its assets in other mutual funds advised by MFS (Massachusetts<br />Financial Services Company, the fund's investment adviser), referred to as<br />underlying funds. The underlying funds are selected following a two stage asset<br />allocation process. The first stage is a strategic asset allocation to determine<br />the percentage of the fund's assets to be invested in the general asset classes<br />of Bond Funds, International Stock Funds, and U.S. Stock Funds, as well as an<br />allocation to underlying funds that have less traditional investment strategies<br />that MFS believes provide diversification benefits when added to a portfolio<br />consisting of stock and bond funds (referred to as Specialty Funds). The second<br />stage involves the actual selection of underlying funds to represent the asset<br />classes based on underlying fund classifications, historical risk, performance,<br />and other factors. Within the stock fund allocations, MFS seeks to diversify<br />globally (by including domestic and international underlying funds), in terms of<br />market capitalization (by including large, mid, and small capitalization<br />underlying funds), and by style (by including both growth and value underlying<br />funds). Within the bond fund allocation, MFS includes underlying funds with<br />varying degrees of interest rate and credit exposure.<br /><br />As of September 28, 2012, the fund's target allocation among asset classes and<br />the underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;60%<br />MFS Emerging Markets Debt Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Global Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Government Securities Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS High Income Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;10%<br />MFS Limited Maturity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;17%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Absolute Return Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;28%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your
family invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.04Your actual after-tax returns will depend on your own tax situation, and
may differ from those shown. The after-tax returns shown are not relevant
to investors who hold their shares through tax-deferred arrangements, such
as 401(k) plans or individual retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may
be required to pay upon purchase or redemption of the fund's shares. If these
sales charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local taxes. <br />Your actual after-tax returns will depend on your own tax situation, and may <br />differ from those shown. The after-tax returns shown are not relevant to investors <br />who hold their shares through tax-deferred arrangements, such as 401(k) plans or <br />individual retirement accounts. The after-tax returns are shown for only one of <br />the fund's classes of shares, and after-tax returns for the fund's other classes <br />of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication
of the risks of investing in the fund by showing changes in the fund's performance
over time and how the fund's performance over time compares with that of a broad
measure of market performance and one or more other measures of performance for
markets in which the fund may invest.<tt>The total return for the six-month period ended June 30, 2012 was 4.93%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 10.76%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (9.28)% (for the calendar quarter ended December 31, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you <br />may be required to pay upon purchase or redemption of the fund's shares. If <br />these sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br /><br />The principal risks of investing in the fund are:<br /> <br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /> <br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /> <br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can <br />already be in default, and their values can decline significantly. Lower quality <br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt <br />instruments.<br /> <br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br /> <br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /> <br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk: The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real estate <br />and the real estate industry in general. These include risks related to general, <br />regional and local economic conditions; fluctuations in interest rates; property <br />tax rates, zoning laws, environmental regulations and other governmental action; <br />cash flow dependency; increased operating expenses; lack of availability of mortgage <br />funds; losses due to natural disasters; overbuilding; losses due to casualty or <br />condemnation; changes in property values and rental rates; and other factors.&#xA0;&#xA0;The <br />securities of smaller real estate-related issuers can be more volatile and less <br />liquid than securities of larger issuers and their issuers can have more limited <br />financial resources.<br /> <br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline significantly <br />in response to issuer, market, economic, industry, political, regulatory, geopolitical, <br />and other conditions, as well as to investor perceptions of these conditions. The <br />price of an equity security can decrease significantly in response to these conditions, <br />and these conditions can affect a single issuer or type of security, issuers within <br />a broad market sector, industry or geographic region, or the market in general.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /> <br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares,
and after-tax returns for the fund's other classes of shares will vary from
the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in <br />the fund's performance over time and how the fund's performance over <br />time compares with that of a broad measure of market performance and <br />one or more other measures of performance for markets in which the fund <br />may invest.<br /><br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses have been adjusted to reflect current fee<br />arrangements.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-20 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002510Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002510Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed
by the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002510Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002510Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Conservative Allocation Fund Blended Index0.04580.03810.05432002-06-28Index Comparisons (Reflects no deduction for fees, expenses or taxes) Barclays U.S. Aggregate Bond Index0.07840.06500.05642002-06-28A Shares Returns After Taxes on Distributions and Sale of Fund Shares -0.02160.02250.03702002-06-28A Shares Returns After Taxes on Distributions-0.04330.02230.03932002-06-28MACNX0.0000R3 Shares Returns Before Taxes1053280.00001259<tt>R3</tt>5690.02360.00090.00000.04510.00250.01030.0103<tt>Class R3 Shares</tt>0.05472002-06-280.0069<tt>ALL R</tt>0.0000MCARX0.0000R2 Shares Returns Before Taxes1304060.00001545<tt>R2</tt>7020.02220.00090.00000.04270.00500.01280.0128<tt>Class R2 Shares</tt>0.05162002-06-280.0069<tt>ALL R</tt>0.0000MACKX0.0000R1 Shares Returns Before Taxes1815600.00002095<tt>R1</tt>9640.01660.00090.00000.03740.01000.01780.0178<tt>Class R1 Shares</tt>0.04682002-06-280.0069<tt>ALL R</tt>0.0000MACIX0.0000I Shares Returns Before Taxes802490.0000966<tt>I</tt>4330.02650.00090.00000.04810.00000.00780.0078<tt>Class I Shares</tt>0.05822002-06-280.0069<tt>I</tt>0.0000MACVX0.0000C Shares Returns Before Taxes2811815600.00002095<tt>C</tt>9640.00640.00090.000020950.0378560964<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.01780.0178<tt>Class C Shares assuming redemption at end of period</tt>0.04772002-06-280.0069<tt>C</tt>0.0100MACBX0.0000B Shares Returns Before Taxes 5811818600.00001897<tt>B</tt>1164-0.02330.00090.000018970.0343560964<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.01780.0178<tt>Class B Shares assuming redemption at end of period</tt>0.04892002-06-280.0069<tt>B</tt>0.0400ECACX0.0000529C Shares Returns Before Taxes286186586-0.00052197<tt>529C</tt>10110.00640.00190.00002013-09-3021970.03645861011<tt>Class 529C Shares assuming no redemption at end of period</tt>0.01000.01830.0188<tt>Class 529C Shares assuming redemption at end of period</tt>0.04582002-06-280.0069<tt>529C</tt>0.0100EBCAX0.0000529B Shares Returns Before Taxes586186886-0.00052001<tt>529B</tt>1211-0.02340.00190.00002013-09-3020010.03305861011<tt>Class 529B Shares assuming no redemption at end of period</tt>0.01000.01830.0188<tt>Class 529B Shares assuming redemption at end of period</tt>0.04692002-06-280.0069<tt>529B</tt>0.0400ECLAX0.0575529A Shares Returns Before Taxes679909-0.00051866<tt>529A</tt>1157-0.03530.00190.00002013-09-300.03140.00250.01080.0113<tt>Class 529A Shares</tt>0.04632002-06-280.0069<tt>529A</tt>0.0000MACJX0.0000R4 Shares Returns Before Taxes802490.0000966<tt>R4</tt>4330.02750.00090.00000.04800.00000.00780.0078<tt>Class R4 Shares</tt>0.05772002-06-280.0069<tt>ALL R </tt>0.0000MACFXthe lowest quarterly returnthe highest quarterly return0.05752012-06-30A Shares Returns Before Taxes 6742009-06-30884-0.09280.07230.00000.11291762<tt>A</tt>11110.07330.1076-0.03460.0009-0.16600.00002008-12-310.22150.03270.0394The total return for the six-month period ended0.02430.11650.00250.01030.01030.0865<tt>Class A Shares</tt>0.04822002-06-280.04930.0069<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.&#xA0;&#xA0;During the most recent fiscal year, the fund's portfolio <br />turnover rate was 6% of the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002507Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002507Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The investment objective of the fund is to seek a high level of total return<br />consistent with a moderate level of risk relative to the other MFS Asset<br />Allocation Funds.&#xA0;&#xA0;(The MFS Asset Allocation Funds currently include the MFS<br />Conservative Allocation Fund, MFS Moderate Allocation Fund, MFS Growth<br />Allocation Fund, and MFS Aggressive Growth Allocation Fund.)</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>The fund is designed to provide diversification among different asset classes by<br />investing its assets in other mutual funds advised by MFS (Massachusetts<br />Financial Services Company, the fund's investment adviser), referred to as<br />underlying funds. The underlying funds are selected following a two stage asset<br />allocation process. The first stage is a strategic asset allocation to determine<br />the percentage of the fund's assets to be invested in the general asset classes<br />of Bond Funds, International Stock Funds, and U.S. Stock Funds, as well as an<br />allocation to underlying funds that have less traditional investment strategies<br />that MFS believes provide diversification benefits when added to a portfolio<br />consisting of stock and bond funds (referred to as Specialty Funds). The second<br />stage involves the actual selection of underlying funds to represent the asset<br />classes based on underlying fund classifications, historical risk, performance,<br />and other factors. Within the stock fund allocations, MFS seeks to diversify<br />globally (by including domestic and international underlying funds), in terms of<br />market capitalization (by including large, mid, and small capitalization<br />underlying funds), and by style (by including both growth and value underlying<br />funds). Within the bond fund allocation, MFS includes underlying funds with<br />varying degrees of interest rate and credit exposure.<br /><br />As of September 28, 2012, the fund's target allocation among asset classes and<br />the underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40%<br />MFS Emerging Markets Debt Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Global Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Government Securities Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS High Income Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%<br />MFS Absolute Return Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;13%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;41%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1.5%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1.5%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.06Your actual after-tax returns will depend on your own tax situation, and may differ from those shown. The after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you
may be required to pay upon purchase or redemption of the fund's shares. If
these sales charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local taxes. <br />Your actual after-tax returns will depend on your own tax situation, and may <br />differ from those shown. The after-tax returns shown are not relevant to investors <br />who hold their shares through tax-deferred arrangements, such as 401(k) plans or <br />individual retirement accounts. The after-tax returns are shown for only one of <br />the fund's classes of shares, and after-tax returns for the fund's other classes <br />of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication
of the risks of investing in the fund by showing changes in the fund's performance
over time and how the fund's performance over time compares with that of a broad
measure of market performance and one or more other measures of performance for
markets in which the fund may invest.<tt>The total return for the six-month period ended June 30, 2012 was 5.90%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 13.80%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (15.13)% (for the calendar quarter ended December 31, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you <br />may be required to pay upon purchase or redemption of the fund's shares. If <br />these sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect a<br />single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br /> <br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the <br />U.S. market. Emerging markets can have less developed markets and less <br />developed legal, regulatory, and accounting systems, and greater political, <br />social, and economic instability than developed markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /> <br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about the <br />issuer, or the market or economy in general, than higher quality debt instruments.<br /><br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /> <br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk:&#xA0;&#xA0;The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real estate <br />and the real estate industry in general. These include risks related to general, <br />regional and local economic conditions; fluctuations in interest rates; property tax <br />rates, zoning laws, environmental regulations and other governmental action; cash <br />flow dependency; increased operating expenses; lack of availability of mortgage <br />funds; losses due to natural disasters; overbuilding; losses due to casualty or <br />condemnation; changes in property values and rental rates; and other factors.&#xA0;&#xA0;The <br />securities of smaller real estate-related issuers can be more volatile and less <br />liquid than securities of larger issuers and their issuers can have more limited <br />financial resources.<br /> <br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in addition <br />to the risks of the underlying indicator(s) on which the derivative is based. Gains <br />or losses from derivatives can be substantially greater than the derivatives' <br />original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares, and after-tax returns for the fund's other classes of shares will vary from the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some<br />indication of the risks of investing in the fund by showing changes in <br />the fund's performance over time and how the fund's performance over <br />time compares with that of a broad measure of market performance and <br />one or more other measures of performance for markets in which the fund <br />may invest.<br /><br />The fund's past performance (before and after taxes) does not necessarily<br />indicate how the fund will perform in the future. Updated performance is<br />available online at mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses have been adjusted to reflect current fee<br />arrangements.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-20 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002507Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002507Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed
by the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002507Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002507Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Moderate Allocation Fund Blended Index0.02220.02300.05372002-06-28Index Comparisons (Reflects no deduction for fees, expenses or taxes) Standard & Poor's 500 Stock Index0.0211-0.00250.04592002-06-28A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.03440.01220.04112002-06-28A Shares Returns After Taxes on Distributions-0.06220.01030.04382002-06-28MAMHX0.0000R3 Shares Returns Before Taxes1113470.00001329<tt>R3</tt>6010.00300.00090.00000.03190.00250.01090.0109<tt>Class R3 Shares</tt>0.05852002-06-280.0075<tt>ALL R </tt>0.0000MARRX0.0000R2 Shares Returns Before Taxes1364250.00001613<tt>R2</tt>734-0.00040.00090.00000.02920.00500.01340.0134<tt>Class R2 Shares </tt>0.05542002-06-280.0075<tt>ALL R</tt>0.0000MAMFX0.0000R1 Shares Returns Before Taxes1875790.00002159<tt>R1</tt>996-0.00530.00090.00000.02420.01000.01840.0184<tt>Class R1 Shares </tt>0.05042002-06-280.0075<tt>ALL R</tt>0.0000MMAIX0.0000I Shares Returns Before Taxes862680.00001037<tt>I</tt>4660.00530.00090.00000.03480.00000.00840.0084<tt>Class I Shares</tt>0.06212002-06-280.0075<tt>I</tt>0.0000MMACX0.0000C Shares Returns Before Taxes2871875790.00002159<tt>C</tt>996-0.01420.00090.000021590.0245579996<tt>Class C Shares assuming no redemption at end of period</tt>0.01000.01840.0184<tt>Class C Shares assuming redemption at end of period</tt>0.05142002-06-280.0075<tt>C</tt>0.0100MMABX0.0000B Shares Returns Before Taxes5871878790.00001962<tt>B</tt>1196-0.04330.00090.000019620.0209579996<tt>Class B Shares assuming no redemption at end of period</tt>0.01000.01840.0184<tt>Class B Shares assuming redemption at end of period</tt>0.05262002-06-280.0075<tt>B</tt>0.0400ECMAX0.0000529C Shares Returns Before Taxes292192604-0.00052260<tt>529C</tt>1042-0.01500.00190.00002013-09-3022600.02306041042<tt>Class 529C Shares assuming no redemption at end of period</tt>0.01000.01890.0194<tt>Class 529C Shares assuming redemption at end of period</tt>0.04952002-06-280.0075<tt>529C</tt>0.0100EBMDX0.0000529B Shares Returns Before Taxes592192904-0.00052066<tt>529B</tt>1242-0.04410.00190.00002013-09-3020660.01966041042<tt>Class 529B Shares assuming no redemption at end of period</tt>0.01000.01890.0194<tt>Class 529B Shares assuming redemption at end of period</tt>0.05072002-06-280.0075<tt>529B</tt>0.0400EAMDX0.0575529A Shares Returns Before Taxes685926-0.00051931<tt>529A</tt>1187-0.05550.00190.00002013-09-300.01830.00250.01140.0119<tt>Class 529A Shares </tt>0.05002002-06-280.0075<tt>529A</tt>0.0000MAMJX0.0000R4 Shares Returns Before Taxes862680.00001037<tt>R4</tt>4660.00530.00090.00000.03450.00000.00840.0084<tt>Class R4 Shares </tt>0.06132002-06-280.0075<tt>ALL R</tt>0.0000MAMAXthe lowest quarterly returnthe highest quarterly return0.05752012-06-30A Shares Returns Before Taxes6802009-06-30902-0.15130.10590.00000.14531827<tt>A</tt>11410.08260.1380-0.05480.0009-0.26040.00002008-12-310.27140.01960.0512The total return for the six-month period ended0.00290.18950.00250.01090.01090.1026<tt>Class A Shares</tt>0.05182002-06-280.05900.0075<tt>A</tt>0.0100<tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.&#xA0;&#xA0;During the most recent fiscal year, the fund's portfolio <br />turnover rate was 11% of the average value of its portfolio.</tt><div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000002506Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/BarChartData_S000002506Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><tt>The investment objective of the fund is to seek a high level of total return<br />consistent with an aggressive level of risk relative to the other MFS Asset<br />Allocation Funds.&#xA0;&#xA0;(The MFS Asset Allocation Funds currently include the MFS<br />Conservative Allocation Fund, MFS Moderate Allocation Fund, MFS Growth<br />Allocation Fund, and MFS Aggressive Growth Allocation Fund.)</tt><tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt>Performance Table.Reflects no deduction for fees, expenses or taxes<tt>The fund is designed to provide diversification among different asset classes by<br />investing its assets in other mutual funds advised by MFS (Massachusetts<br />Financial Services Company, the fund's investment adviser), referred to as<br />underlying funds. The underlying funds are selected following a two stage asset<br />allocation process. The first stage is a strategic asset allocation to determine<br />the percentage of the fund's assets to be invested in the general asset classes<br />of Bond Funds, International Stock Funds, and U.S. Stock Funds, as well as an<br />allocation to underlying funds that have less traditional investment strategies<br />that MFS believes provide diversification benefits when added to a portfolio<br />consisting of stock and bond funds (referred to as Specialty Funds). The second<br />stage involves the actual selection of underlying funds to represent the asset<br />classes based on underlying fund classifications, historical risk, performance,<br />and other factors. Within the stock fund allocations, MFS seeks to diversify<br />globally (by including domestic and international underlying funds), in terms of<br />market capitalization (by including large, mid, and small capitalization<br />underlying funds), and by style (by including both growth and value underlying<br />funds).<br /><br />As of September 28, 2012, the fund's target allocation among asset classes and<br />the underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30%<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;60%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;13%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2.5%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2.5%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;9%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;13%</tt>Summary of Key InformationYou may qualify for sales charge reductions if you and certain members of your
family invest, or agree to invest in the future, at least $50,000 in MFS Funds.ExampleAfter-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.Investment ObjectiveThe fund's past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future.As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund.Principal RisksShareholder Fees (fees paid directly from your investment):Although your actual costs will likely be higher or lower, under these assumptions your costs would be:0.11Your actual after-tax returns will depend on your own tax situation, and may
differ from those shown. The after-tax returns shown are not relevant to
investors who hold their shares through tax-deferred arrangements, such as
401(k) plans or individual retirement accounts.Class A Bar Chart.The bar chart does not take into account any sales charges (loads) that you may
be required to pay upon purchase or redemption of the fund's shares. If these
sales charges were included, they would reduce the returns shown.Performance Information50000<tt>After-tax returns are calculated using the historical highest individual federal<br />marginal income tax rates and do not reflect the impact of state and local<br />taxes. Your actual after-tax returns will depend on your own tax situation, and<br />may differ from those shown. The after-tax returns shown are not relevant to<br />investors who hold their shares through tax-deferred arrangements, such as 401(k) <br />plans or individual retirement accounts. The after-tax returns are shown for only <br />one of the fund's classes of shares, and after-tax returns for the fund's other <br />classes of shares will vary from the returns shown.</tt>The bar chart and performance table below are intended to provide some indication of the risks of investing in the fund by showing changes in the fund's performance over time and how the fund's performance over time compares with that of a broad measure of market performance and one or more other measures of performance for markets in which the fund may invest.<tt>The total return for the six-month period ended June 30, 2012 was 7.42%. During<br />the period(s) shown in the bar chart, the highest quarterly return was 19.81%<br />(for the calendar quarter ended June 30, 2009) and the lowest quarterly return<br />was (24.63)% (for the calendar quarter ended December 31, 2008).</tt>1-800-225-2606Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):Average Annual Total Returns (for the Periods Ended December 31, 2011)<tt>The bar chart does not take into account any sales charges (loads) that you <br />may be required to pay upon purchase or redemption of the fund's shares. If <br />these sales charges were included, they would reduce the returns shown.</tt>Portfolio Turnover<tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund. An investment in the fund is not a<br />bank deposit and is not insured or guaranteed by the Federal Deposit Insurance<br />Corporation or any other governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect a<br />single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br /> <br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets and less developed<br />legal, regulatory, and accounting systems, and greater political, social, and<br />economic instability than developed markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br />&#xA0;&#xA0;<br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk:&#xA0;&#xA0;The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real <br />estate and the real estate industry in general. These include risks related to <br />general, regional and local economic conditions; fluctuations in interest rates; <br />property tax rates, zoning laws, environmental regulations and other governmental <br />action; cash flow dependency; increased operating expenses; lack of availability <br />of mortgage funds; losses due to natural disasters; overbuilding; losses due to <br />casualty or condemnation; changes in property values and rental rates; and other <br />factors.&#xA0;&#xA0;The securities of smaller real estate-related issuers can be more volatile <br />and less liquid than securities of larger issuers and their issuers can have more <br />limited financial resources.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in addition <br />to the risks of the underlying indicator(s) on which the derivative is based. Gains <br />or losses from derivatives can be substantially greater than the derivatives' <br />original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt>Fees and ExpensesThe after-tax returns are shown for only one of the fund's classes of shares,
and after-tax returns for the fund's other classes of shares will vary from
the returns shown.Principal Investment Strategiesmfs.com<tt>The bar chart and performance table below are intended to provide some indication <br />of the risks of investing in the fund by showing changes in the fund's performance <br />over time and how the fund's performance over time compares with that of a broad <br />measure of market performance and one or more other measures of performance for <br />markets in which the fund may invest.<br /><br />The fund's past performance (before and after taxes) does not necessarily indicate <br />how the fund will perform in the future. Updated performance is available online at <br />mfs.com or by calling 1-800-225-2606.</tt><tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. Expenses have been adjusted to reflect current fee<br />arrangements.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 9 of the fund's prospectus and "Waivers of Sales Charges" on page I-20 of<br />the fund's statement of additional information Part I.</tt><div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000002506Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/PerformanceTableData_S000002506Member column dei_LegalEntityAxis compact * column rr_PerformanceMeasureAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>An investment in the fund is not a bank deposit and is not insured or guaranteed
by the Federal Deposit Insurance Corporation or any other governmental agency.<div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000002506Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div><div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000002506Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div>Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Aggressive Growth Allocation Fund Blended Index-0.0332-0.01250.04762002-06-28Index Comparisons (Reflects no deduction for fees, expenses or taxes) Standard & Poor's 500 Stock Index0.0211-0.00250.04592002-06-28A Shares Returns After Taxes on Distributions and Sale of Fund Shares-0.0656-0.01180.03992002-06-28A Shares Returns After Taxes on Distributions-0.1068-0.01790.04272002-06-28MAAHX0.0000R3 Shares Returns Before Taxes126398-0.00021521<tt>R3</tt>690-0.05000.00150.0000-0.00110.01240.0126<tt>Class R3 Shares</tt>0.05322002-06-280.0086<tt>ALL R</tt>0.0000MAWAX0.0000R2 Shares Returns Before Taxes152475-0.00021800<tt>R2</tt>822-0.05270.00150.0000-0.00370.00500.01490.0151<tt>Class R2 Shares</tt>0.05022002-06-280.0086<tt>ALL R </tt>0.0000MAAFX0.0000R1 Shares Returns Before Taxes202629-0.00022336<tt>R1</tt>1081-0.05700.00150.0000-0.00850.01000.01990.0201<tt>Class R1 Shares</tt>0.04532002-06-280.0086<tt>ALL R </tt>0.0000MIAGX0.0000I Shares Returns Before Taxes101320-0.00021234<tt>I</tt>556-0.04820.00150.00000.00170.00000.00990.0101<tt>Class I Shares</tt>0.05682002-06-280.0086<tt>I</tt>0.0000MCAGX0.0000C Shares Returns Before Taxes302202629-0.00022336<tt>C</tt>1081-0.06610.00150.00002336-0.00826291081<tt>Class C no redemption at end of period</tt>0.01000.01990.0201<tt>Class C Shares assuming redemption at end of period</tt>0.04632002-06-280.0086<tt>C</tt>0.0100MBAGX0.0000B Shares Returns Before Taxes602202929-0.00022143<tt>B</tt>1281-0.09530.00150.00002143-0.01186291081<tt>Class B Shares no redemption at end of period</tt>0.01000.01990.0201<tt>Class B Shares assuming redemption at end of period</tt>0.04772002-06-280.0086<tt>B</tt>0.0400ECAAX0.0000529C Shares Returns Before Taxes307207654-0.00072436<tt>529C</tt>1128-0.06710.00250.00002013-09-302436-0.00966541128<tt>Class 529C no redemption at end of period</tt>0.01000.02040.0211<tt>Class 529C Shares assuming redemption at end of period</tt>0.04432002-06-280.0086<tt>529C</tt>0.0100EBAAX0.0000529B Shares Returns Before Taxes607207954-0.00072245<tt>529B</tt>1328-0.09590.00250.00002013-09-302245-0.01326541128<tt>Class 529B no redemption at end of period</tt>0.01000.02040.0211<tt>Class 529B Shares assuming redemption at end of period</tt>0.04522002-06-280.0086<tt>529B</tt>0.0400EAGTX0.0575529A Shares Returns Before Taxes699974-0.00072110<tt>529A</tt>1271-0.10610.00250.00002013-09-30-0.01430.00250.01290.0136<tt>Class 529A Shares</tt>0.04502002-06-280.0086<tt>529A</tt>0.0000MAALX0.0000R4 Shares Returns Before Taxes101320-0.00021234<tt>R4</tt>556-0.04800.00150.00000.00150.00000.00990.0101<tt>Class R4 Shares </tt>0.05612002-06-280.0086<tt>ALL R</tt>0.0000MAAGXthe lowest quarterly returnthe highest quarterly return0.05752012-06-30A Shares Returns Before Taxes6942009-06-30950-0.24630.1521-0.00020.18452008<tt>A</tt>12250.09230.1981-0.10440.0015-0.40480.00002008-12-310.3587-0.01290.0732The total return for the six-month period ended-0.04980.31880.00250.01240.01260.1306<tt>Class A Shares</tt>0.04672002-06-280.07420.0086<tt>A</tt>0.01000000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006838Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006839Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006840Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006841Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006842Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006843Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006844Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006845Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006847Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006849Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:C000006850Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006838Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006838Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:RRINDEX00001Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Memberck0000783740:RRINDEX00002Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002506Memberck0000783740:S000002506Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006851Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006852Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006853Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006854Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006855Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006856Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006857Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006858Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006860Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006862Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:C000006863Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006851Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006851Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:RRINDEX00001Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Memberck0000783740:RRINDEX00003Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002507Memberck0000783740:S000002507Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006887Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006888Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006889Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006890Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006891Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006892Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006893Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006894Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006896Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006898Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:C000006899Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006887Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006887Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:RRINDEX00004Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Memberck0000783740:RRINDEX00005Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002510Memberck0000783740:S000002510Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000006904Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000006905Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000006906Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000006907Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000071424Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000071425Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000071426Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000071427Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:C000071428Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006904Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006904Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Memberck0000783740:RRINDEX00006Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002512Memberck0000783740:S000002512Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006911Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006912Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006913Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006914Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006915Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006916Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006917Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006918Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006920Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006922Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:C000006923Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006911Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006911Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:RRINDEX00001Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Memberck0000783740:RRINDEX00007Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002514Memberck0000783740:S000002514Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006924Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006925Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006926Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006927Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006928Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006929Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006930Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006931Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006933Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006935Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:C000006936Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006924Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006924Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Memberck0000783740:RRINDEX00008Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002515Memberck0000783740:S000002515Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000006937Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000006938Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000006939Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000006940Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000034484Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000071430Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000071431Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000071432Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:C000071433Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006937Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006937Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Memberck0000783740:RRINDEX00008Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002516Memberck0000783740:S000002516Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000006941Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000006942Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000006943Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000006944Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000034485Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000071434Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000071435Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000071436Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:C000071437Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000006941Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000006941Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:RRINDEX00009Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Memberck0000783740:RRINDEX00010Member2012-09-282012-09-280000783740ck0000783740:SummaryS000002517Memberck0000783740:S000002517Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088935Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088936Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088937Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088938Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088939Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088940Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088941Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000088942Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:C000120923Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberrr:AfterTaxesOnDistributionsMemberck0000783740:C000088935Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberrr:AfterTaxesOnDistributionsAndSalesMemberck0000783740:C000088935Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Memberck0000783740:RRINDEX00011Member2012-09-282012-09-280000783740ck0000783740:SummaryS000028956Memberck0000783740:S000028956Member2012-09-282012-09-280000783740ck0000783740:SummaryS000031672Memberck0000783740:S000031672Memberck0000783740:C000098544Member2012-09-282012-09-280000783740ck0000783740:SummaryS000031672Memberck0000783740:S000031672Memberck0000783740:C000098545Member2012-09-282012-09-280000783740ck0000783740:SummaryS000031672Memberck0000783740:S000031672Memberck0000783740:C000098546Member2012-09-282012-09-280000783740ck0000783740:SummaryS000031672Memberck0000783740:S000031672Memberck0000783740:C000098547Member2012-09-282012-09-280000783740ck0000783740:SummaryS000031672Memberck0000783740:S000031672Memberck0000783740:C000098548Member2012-09-282012-09-280000783740ck0000783740:SummaryS000031672Member